/Engine/Plugins/Animation/IKRig/Source/IKRigEditor/Public/RigEditor/IKRigController.h
Get the name of the root bone on a given solver. (not all solvers support root bones, checks CanSetRootBone() first)
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=IKRig) [FName](API\Runtime\Core\UObject\FName) GetRootBone ( int32 SolverIndex ) const